Acute Hypoxia From Different Clinical Entities Can Potentially Break the Heart: Takotsubo Cardiomyopathy.

Takotsubo syndrome is characterized by transient regional left ventricular wall motion abnormalities and elevated troponin levels like those seen in classic myocardial infarction but without evidence of obstructive coronary artery disease. We present two uncommon cases of Takotsubo syndrome. In Case 1, a 64-year-old man presented with chronic obstructive pulmonary disease exacerbation who later developed chest pain and acute hypoxic respiratory failure. In Case 2, a 77-year-old woman with myasthenia gravis was admitted for acute hypoxic hypercapnic respiratory failure requiring mechanical ventilation following a myasthenic crisis. In both cases, serum high sensitivity troponin was elevated, electrocardiograph showed findings suggestive of infarction, and coronary angiogram did not show evidence of obstructive coronary artery disease. Echocardiogram in both patients revealed abnormal left ventricular wall motion, likely secondary to Takotsubo syndrome. Takotsubo syndrome is uncommon in the setting of chronic obstructive pulmonary disease exacerbation or myasthenic crisis, and proposed mechanisms for the disease include catecholamine surge, vasospasm of coronary arteries, and microvascular dysfunction. Takotsubo syndrome is reversible; thus, it is important to remove any trigger leading to catecholamine surge. Identification of such triggers and early diagnosis could help optimize pharmacotherapy.